1. Field of Invention
The present invention relates to an integrated circuit process, and more particularly to a removing process.
2. Description of Related Art
An etching process is a commonly used method to remove a film layer in a semiconductor process. The etching process generally includes a wet etching and a dry etching. The wet etching provides a higher etching selectivity and is suitable for an isotropic etching process. However, it is difficult to obtain a vertical structure through the wet etching. When more and more devices are developed toward high aspect ratio structures, the dry etching is adopted due to its excellent performance. Besides, the dry etching has the advantages of better control of etching rate, precise etched dimension and high degree of automation etc.
However, with the continued miniaturization of a device size, by-products generated by the dry etching process are easy to remain in small gaps between patterns. Therefore, the undesired thickness of the material layer below the gaps can not be etched completely, and the serious loading effect and other issues occur.